Hereinafter, a compressed gas cartridge will be referenced as a cgc.
Many people use compressed gas dispensers daily in a variety of applications such as medical, commercial, and domestic. Common uses of such a dispenser are for use in the medical industry. Exemplary medical industry devices include: pneumatic inflation, cryogenic-related devices, pneumatic staple devices and dry powder and wet inhalers.
Good hospital hygiene practices frequently include incineration of used disposable medical devices in order to minimize the hazards of infectious waste. CGC's, particularly those filled with compressed carbon dioxide or nitrous oxide retain in the range of 700 to 900 psi, depending on room temperature. Introduced heat quickly raises cgc pressure. For example, raising a cgc of carbon dioxide to 140 degrees Fahrenheit increases the cgc pressure to about 3400 psi while a cgc of carbon dioxide at 160 degrees Fahrenheit yields about 4200 psi. These temperatures/pressures exceed cartridge manufacturer's specified safe temperature range and have now become a dangerous pressure vessel waiting to violently explode. Typically, a steel cgc will not gradually release high pressure because the cartridge sealing cap is welded into place to form an all metal sealed pressure vessel. Instead, the sudden release of pressure upon explosion causes the cgc to become a projectile, randomly sending shrapnel into the air, and creating dangerously high decibel noise, capable of permanently damaging one's ears.
Some incinerators are armored to protect personnel and equipment should a full cgc accidentally be added to the furnace. Incinerator temperatures can quickly bring a cgc temperature up to dangerous levels in minimal time, perhaps within seconds of introduction to the heat.
There are many commercial and domestic uses of cgc's and a few exemplary applications include: tire inflation, portable pneumatic tool applications, actuators—by heat, manual, electronic, and other methods, air guns, life preserver inflation, aircraft redundant pneumatic systems, and more.
Some of these applications are potentially subjected to intense heat that could result in dangerous explosion of a cgc thus causing user injury and property damage. For example, a cyclist may leave a cgc dispenser in a car on a hot day with the windows rolled up. CGC's can, and do, occasionally rapidly explode in a hot vehicle which is overall, an undesirable event. A portable pneumatic tool may be left out in the sunlight for a period of time. The intense heat buildup can cause a cgc to reach dangerous temperatures.
In summary, there has been a long felt need for a safety feature that prevents a cgc from reaching dangerously high pressures should a cgc be subjected to high heat while installed in a dispenser head.
Two distinct types of cgc's are currently common—threaded neck portion and non-threaded neck portion. Many current art compressed gas dispensers, particularly the models manufactured by Genuine Innovations, Inc. in Tucson, Ariz. U.S.A. are manufactured to dispense a non-threaded neck compressed gas cartridge, dispense a threaded neck compressed gas cartridge, or capable of dispensing both species within the same dispenser.
One feature of current art compressed gas dispensers is a lance housing that has been used in part to contain the high pressure from a compressed gas cartridge. Historically, lance housings have been manufactured from metal such as brass. A lance housing also provides an excellent recess or pocket for a seal that is used to contain the compressed gas in a lanced cartridge and studying the prior-art exemplifies many methods of virtually accomplishing the same sealing result. A lance housing can feature internal threads that are used to mate with a compressed gas cartridge also exhibiting a threaded neck portion and a lance housing sometimes exhibits no threads to mate with a compressed gas cartridge and can accept only non-threaded varieties.
U.S. Pat. No. 6,843,388 by Hollars titled Compressed gas cartridge dispensing system allowing interchangeable use of different capacity compressed gas cartridges and novel storage feature teaches some methods of how a non-threaded neck compressed gas cartridge can be dispensed as well as teaches an additional method of how a threaded neck compressed gas cartridge can be dispensed. Additionally, the terminology from the U.S. Pat. No. 6,843,388 is carried over into this application in an effort to maintain consistency for ease of understanding.
The preferred embodiment and alternative embodiments will be exemplified in the following paragraphs and in the FIGS. The following embodiments will describe the afore-mentioned prior-art and the present invention. Additionally, with the aid of figures, one skilled in the art will be able to understand and appreciate the scope of the exemplary embodiments to follow.